Mitigation techniques to limit human exposure to EMFs in the vicinity of radiocommunication stations
|Publication Date:||1 June 2007|
This Recommendation provides guidance on mitigation techniques for limiting the exposure from radiocommunication installations, especially in the multiple sources environment. This guidance presents methods for field strength distribution evaluation, cumulative exposure ratio evaluation, identification of the main source of radiation, and offers mitigation techniques - methods for reducing the levels of electromagnetic fields during simultaneous exposure in the multiple sources environment.
In this Recommendation, the following reference limits are used: electric field strength, magnetic field strength and power density. Since compliance with the reference limits guarantees the compliance with basic restrictions, this is a conservative approach. In the far-field region the use of the reference levels gives results which are very close to real radiation levels. In the near-field region the obtained results will overestimate or underestimate real radiation levels. Moreover, this Recommendation deals with reference levels calculated in free space, so EMF influence on human tissues or human body is not considered.
This Recommendation also gives guidance on identifying those areas in which the highest radiation levels should be expected. This piece of information may be helpful to define the area for measurements.
The guidance given in this Recommendation applies to any exposure limits; however, in the examples of calculations, the ICNIRP exposure limits are taken.
A software EMF-estimator (see Appendix I) is attached to this Recommendation in order to support its application. The software implements the methodology described in this Recommendation and gives the possibility to calculate the cumulative exposure for the reference levels. It also contains the library of the radiation patterns of transmitting antennas for a wide range of radiocommunication and broadcast services. The EMF-estimator is not appropriate for the equipment certification in order to put it on the market.
This Recommendation is intended for use when considering the EMFs in areas around transmitting stations, e.g., around transmitting antennas in their places of installation.